Resistance unit



Patented Nov. 12 1935 REBISTANCE UNI'J.

lreclerlc H. Bullinger, Brimxxllle, N. Y. uaignor to Wud Leonud Elecirlc(lonunny, a corpoutlon otNew York Mnflhnflon nu 17. 19:3, SGll&l N0.071.43: Chinas. (Ch zo 1 as) 'I'his lnvention particularly relates isoan improved tubular resistance unit und method ot making the samewherein the reeisi:ive conductor is wound 011 a hollow insuiating tubeend in which the tube also'senes to carry the terminels to which theresistive conductor is connected.

'I'he mein object oi' the invention is to produce a resistanoe unit o!the tubular type which is adapted to be rea.dily manufactured a.tcompanl0 tiveiy low cost, while, at the sa.me time. producing an articlewhich is dependable in Ion: continued use end satisfactory in variousother oommercial requirements. 'I'he economy in cost oi' production issecured not only by convenience und rupidityi-S inmaking, but also byuse ot e form 01 terminalconnection which permits the cool: o! materla.ltonning the terminai connection to be low. Another object is to providea. Ion-m o! ter'miml umnection which, although simple in character. will20 not be displaced er disturbed in ordinuy nasse end which will form a.permanent good electrical eoxmection with the resistive oonducinor.Another objectis to avoid the use oi my cloaed circuited coiljor bandaround the tube in forminzhe ter- 25 mina.l connection or connections,es auch commonly used coils or bands ere alten objectionnble when theresistive unit in uaed in connection with high'irequency apperetus.Another object is to provide a resistive unit which will lnve a smooth3') end plea.sing eppeqrence withou t objectionnble protuberances. Otherobjects end advantages o! the invention will be understnod by thoseskilled in the art fromthe ioliowing desc'ription und accompanyingdre.wing which illustretes preterred embodiments o! the inventlon.

I"igure 1 is a. longitudinal lecti0n 01 a ux'xit showing the mounting 01the terminals thereip. Fix. 2 in an end view ot the structure shown inFig. l. Fix. 3 is s bottom view 01 the structure 40 ahown in I"ig. 1 endalso showinz the resistive canductoripplied to the tube end connected tothe terminals. Fix. 4 is a side view oi the completed unit. Fix. 5 is aside view showing the resistive conductor on the tube und connected to adifler- 43 eni: part 01 the lead irom thai: 5hown in Fix. 3 und-oppbsite. A bendable ieadis used which passe:

through oppositely located holes in the tube end.

in order to hold the sa.me in place on the tube. the iead i.s bent atthe inne:- surface o! the tube so a.s to form a loop for holding thesame in position. 5 Thusaleadinligs. land2isshownatlinthe i'orm 018 a.copper wire having an unter end 2 In: convenient oonnectiou 1:0 otherdevices or conductors. 'I'his copper wire is shown es paasinz throughtwo opposiizely located holes near the end ot the tube landisbentwithinthehxbetotorm a. loop 2. 'l'his bend or loop inthewire-is sufliciently pronounced to insure the lea.d being held inplace on the tube und may be i'onned by pushing e cone-shaped tool inthe end cf the tube. or otherwise.- One end 2 01 the wire terminal lsshown pr0iectin: a little beyond the suriace o! the tube ior connectionthereto oi' the resistive eonduciaor. At the opposite end o! the tube inshown another lea.d wit 'e I hflinl the Wndin: perts 3. I end 1. 1

Fix. 3 shows the resistive conductor l applied to the insuletin: supportDein: wound thereon und havin: its ends connected tothe leacl wires.

Ili epplylnz the reaktive donductor. oue endthereoiisgivenatewturnsaround theend3 01 one o! the terminals und theni.s wo1md wund the tube intheusalwutotheendloftheotherterminnlandiscivenafewturnsamundthisendsoasto be secured thereto. In order toserve es a. guide for the ends oi' the resistive conductor. & murow slot5 i.s tormed circumierentially on the insulating tube end ecross theopenings which receive the ende 2 und 3 01 the lea.d wires, these slotsbeing cut in the taube betone the ieed wires ue placed in position. Timswhen the end o! the resistive conductor is wrapped around the end 3. theconductor then nasses through end is lodzed in one portion 01 the slot 5es it passes trom the end 3 around the tube. Similariy when theend 40 o!the condudtor reaches the other end 01 the tube lt will pa.ss in inclthxough one portion o! the slot 5 end then be wrapped around the end 2.These guiding 'slots i'or the! registive conductor are not essential butere convenient tor pro:ierly locating und directing the conductor. 'lheslot in also utilized in hold the end 01 the lea.d in plaoe. l'ho ends 2und 8 a.re preterably flattened so es to i'.lt snugly in the slots,thereby preventing a.ny movement ot, the lead which might breal: theresistive conductor during oi alter the process 01 manutacture. Afterbeing thus assembled, theresistive conductor i.s preierdbly soldered tothe lead wirea havlng a comparatlvely hlgh melting point, such as a hightemperature silver solder.

I'he unit is next covered with an lnsulatlng coating on the externalsurface of the tube so as to insulate and protect the resistlveconductor from mechanical lnjury and moisture in the usual way. Thiscoating ls preferably an adheslve vitreous enamel as it firmly adheresto the parts, has high lnsulating qualities and ls lmpervlous tomoisture. The enamel material alter belng applied to the unlt so as tocover the small projections 2 and 3 and also the base of the lead wireswhere they extend outwardly from the tube, ls matured in a Iurnace toproduce the flnlshed product, such as shown in Flg. 4. The externalsurface of the tube has a smooth appearance wlth only slight projectionswhere the connectlon 01 the resistive conductor ls made at the ends 2and 3.

Instead of connecting the resistive conductor to the and 2 or 3 of thelead wire, the conductor may be connected to the lead at the point wherethe mein portion leaves the taube. Thus in Flg. 5 the resistiveconductor is wrapped around the lead 3 at the polnt 1 and solderedtheteto and similarly a1; the.point 8 of the lead 2. Likewise, the slot5 would be Iormed in the tube at the polnt where the mein part 015 thelead leaves the tube, for guidlng the resistive conductor and holdlngthe flattened lead in place. In the iorm shown in Flg. 5, the projectlngends, such as 2 and 3 are avolded so that the tube at such points has asmooth external appearance without any materlal projections. Thls formo1 tube in completed form is shown in Fix. 6.

Alt-hough I have shown the leads located at the -ends 01 the tube, lt isevident that one or more may be located at intermediate polnts along thelength of the tube and the reslstlve conductor connected thereto, asalready described, where lt ls desired that the unit be supplied wl thtaps. It will also be understood that instead oI the leads, such as 2,3, belng formed of a solld copper wire, they may be 01 other forms 01'of other material; likewise the termlnal instead of havlng outwardlyextended portlons for connectlon to an external circuit, may beconnected to other forms 01 external termlnals and serve as anchorlngmeans or intermediate connection, therefor. Also, the leads may be bentat the outslde suriaoe o! the tube, or enlarged or flattened at theoutslde surface of the tube to hold the same in place.

Although I-have described particular lmprovements of my invention, ltwill be understood that various modifications and adaptatlons may bemade wlthout departlng Iroxn the scope of my inventlon.

I claim:-

1. A resislzance unlt cor'nprlsing an insulatlng tube, a reslstiveelement thereon, and a terminal to which said resistive element iselectri'cally counected, said termlnal extending across the interior o!the tube substantially in a plane perpendioular to the axis 015 the tubeand belng bent wlthin the tube to hold lt in place, and extendingoutwardly from the tube to !orxn an external terminal.

2. A reslstance unlt comprlslng an insulating taube, a reslstlve elementthereon, and a terminal to which said resistlve element is electrlcallyconnected, said tube having a pair of openings extending from theoutside o! the tube to the inside 015 the tube, and said terminalpasslng through said openings and across the lnterlor 015 the tubesubstantially in a plane perpendlcular to the axls of the tube and beingbent withln the tube to hold lt in place.

3. A reslstance unit comprlsing an insulating tube, a reslstlve elementthereon, and a termlnal to whlch said resistlve element is electrlcallyconnected, said tube having a pair ot openings extending trom theoutside 015 the tube to the lnside o! the tube, and said termlnalpasslng through said openings and across the lnterlor 01 the tubesubstantially in a plane perpendlcular 1:0 the axis 01 the tube andbeing bent within the tube to hold it in place, and extending outwardlyfrom the tube to forxn an external terminal.

4. A resistance unlt comprlsing an insulating tube, a resistiveelemer'it thereon, and a termlnal to which said resistlve element iselectrically counected, said tube having a pair o! dlametrically opposedopenings extendlng from the outslde o! the tube to the inslde 015 thetube, and said terminal passlng through said openings and across theinterlor of the tube and being bent wlthln the tube to hold it in place.

5. A resistance unlt comprlsing an insulating tube, a resistlve elementthereon, and a termlnal to which said resistlve element ls electricallycounected, said tube havlng a pair of openlngs extendlng from theoutslde 013 the tube to the lnslde of the tube and located substantiallyin a plane perpendicular to the axis 01 the tube, and said tennlnalbeing in the forrn of a wire passlng through said openlngs and acrossthe interlor of the tube and being bent wlthln the tube to hold lt Inplace. 6. A resistance unic, comprislng an insulating tube, a resistlveelement thereon, and a terminal to whlch said reslstive element iselectrically counected, said tube having a nah of dlametrlcally opposedopenlngsextendlng from the outslde 01 the tube to the inside 01 thetube, and said terminal being In the Iorm 01 a wire passlng through saidopenings and across the interior of the tube and belng bent wlthln thetube to hold lt in place and extending outwardly (mm the tube to form anexternal connectlon.

7. A reslstance unlt comprlsing an lnsulatlng tube, a reslstlve elementthereon, and a terminal to whlch said reslstlve element is electricallyconnected, said termlnal extendlng through two walls o! the taube andacross the lnterlor ot the tube substantlally in a plane perpendlcularto the axis of the taube and belng bent to hold the saxne in flxedposltion on the tube.

8. A resistance unlt comprlsing an insulatlng taube, a reslstlve elementthereon, and a termlnal to which said resistlve elementls electrlcallyconnected, said tube having a pair 015 openings extendlng from theoutside 01 the tube to the inside 015 the tube and located substantiallyin a plane perpendlcular to the axls 01 the tube, and said terminalpassing through said openlngs and across the Interim 01 the tube andbelng bent to hold the same in fixed position on the tube.

9. A resistance unlt.doxhprislng an lnsulating tube, a resistive elementthereon, and a termlnal to whlch said reslstlve element is electricallyconnected, said tube having a palr 01 openings extending Irom theoutside 01 the tube to the inside of the tube and located substantiallyin a. plane perpendlcular to the axis o! the tube, and sald terminalpassing through said openings and across the lnterlor 01 the tube andbeing bent to hold the same in flxed positlon on the tube and extendingoutwardly Irom the tube to Iorm an external termlnal.

FREDERIC H. BULIJNGER.

